Product courtesy of Seng Chu Hin
Ever heard of Precision Billet? The American company responsible for CNC machined, anodized deraillers and the Bombshell brand of forks also set up Da Bomb bikes. The frames and various bike parts are designed in the US and manufacturing outsourced to Taiwan. This keeps the costs way low and affordable, yet allows at least decent, if not, high quality of construction. In fact, Da Bomb products are made for the serious rider and every frame or component design is tested and fine tuned by sponsored teams before they are introduced to the public. The quality of Da Bomb frames is reflected in the popularity of the brand in Europe, Australia and even here in Singapore. Take a look around at any local dh, slalom or trials comp. You’d probably see a Da Bomb, if not a few of them. From an entire stable of freeride, dh, slalom/ BSX bikes, we were given the opportunity to put our dirty mitts on Da Bomb’s latest project – A 4130 cromoly dirt jump frame called CR8 ( short for Create ).
Usually sold frame only, the test bike came with some choice bits. Tough Truvativ Hussefelt cranks, incredibly strong 24″ prototype Da Bomb 6061 chrome-plated rims ( now available in the ’03 line ), positive shifting Sram XO rear derailler and Armor hydraulic disc brakes ( which received really good reviews in Australian Mountain Bike magazine ). Other parts hanging off the frame were a Psylo C fork and some Da Bomb and FUNN components.
Sitting on the bike feels just like sitting on a bmx cruiser, albeit one with some gears and a bouncy fork. The small 13.5″ frame aroused most people’s interested the moment they sat on it! You instinctively get the feeling that this would be one nippy fun bike. Even the bmxers were not spared the seduction and some expressed an interest in the bike. That was a compliment in itself!
A close look at the frame shows much attention to detail and a few interesting features that tell you that this frame was designed by someone who actually rides, and not only that, but uses it for dirt jumps. Double butted 4130 tubing keeps the weight low yet sacrifices little strength. That should make tabletops and other whipping stuff much easier, allowing you to fly higher and go faster as well. Aluminium tubing may look all big and impressive, but if you want to dirt jump, catastrophic failure’s the last thing you’d want. Cromo’s the one and only choice!
The lengths and angles were pretty standard ( as compared to most other jump bikes ) with the frame working best with a short to medium travel fork. You could get by with a 5″ fork, but it’ll turn slowly. That really kills the lively feel of the bike. Chainstays were 17″ which meant that it wouldn’t exactly be much of a sprinter. But then again, you’d be able to fit in those 24″ by 3.0″ tires if you ever wanted a cushy rear for all the street stuff. Going large to flat on concrete can be a chore on the back after a while… However, with the 24″ wheels and a decently short wheelbase, the bike manuals and wheelies quite well. Definitely much better than with 26″ wheels on, and definitely fun enough that you’d want to manual everything and wheelie everywhere. Even manualling stairs was fun! But of course, the option to run 26″ wheels is there although I’d just stick to 24″.
The tubing on the CR8 may look fragile to most who’re used to looking at aluminium tubing, but they’re strong enough. In fact, the CR8 is a stronger frame than most aluminium jump bikes out there. Those thick dropouts would take a severe beating, and there’re even top, bottom and side transfer gussets at the headtube junction. The headtube is reinforced to prevent flaring and the replaceable dropouts are forged and shot-peened steel. Scratches and little dents in the frame would not affect it catastrophically like aluminium. The chainstays and seatstays are made from decently large tubing which give a pretty rigid rear yet taking the sting out of landings like the best cromo frames should. It never fails to amaze me when I go jumping on a cromo frame. The liveliness and innate spring in the frame is something that many modern riders will never know.
Cable layout is a very neat under-the-top-tube routing with stops large enough to run hydraulic cables and full length derailler housing. Don’t want to snag a foot in the cables whilst doing a “can can” now, don’t we?… The CR8 also comes in a different heavier, stronger version with horizontal dropouts called CR8-BMX ( although it’s still a mtb ). At the cost of SD$350 a frame, this is probably the cheapest 4130 frame around! Every other comparable 4130 frame costs at least SD$450. Even the budget aluminium jump frames are not as affordable.
Close inspection of the frame revealed several slight imperfections. The paint work’s on the thin side and paint on the rims of the headtube the BB shell and the disc brake mount need to be sanded off a tad before building up the bike. Frame stickers were not covered by the lacquer coat, leaving them vulnerable, weldings were not tidy or very straight in places, however they were adequate and only a cosmetic issue. And that was it! All in all, a surprisingly well made and well thought out budget frame with lots of attention to detail.
The Nature of the Bike
There are two ways to build up a dirt jump frame. 1) Do it up strong and reasonably weighted, 2) Make it ultra beefy and bombproof. There are advantages to both schools of thought, although the more hardcore pure dirt jump riders would go the bombproof route. The CR8, being double butted and all belongs to the former category. It is a frame with which you have to maintain some fluidity on the landings and one which would not withstand seriously high mid-air bails everyday. However, the strength is still there. You can put heavy cromo components on it, convert it to single speed if you so please, and go ditch the thing in the event of a big botch up in mid-flight. Just don’t do that too often though… It all depends on how high you usually fly, I guess. The regular dirt jumper should find it more than adequate. And of course, it’s stronger and more appropriate than most aluminium frames for dirt jumping…
Size does matter. In this case, the small frame felt so much like a bmx cruiser. The bike pretty much didn’t get in the way at all whilst jumping. The frame is pretty flickable in the air, changing attitude when you nudge it. So much so that it almost flies exactly the way you want it to go and becomes part of you. Just think of what you want to do and more often than not, it’s behaving as you’d wished! Being on the light side for a cromo dirt jump frame also means that you get up to speed faster, with less effort, and fly higher. This all translates to more time having fun and less time catching your breath.
The relatively light weight allows versatility in function. The frame does well in street and even as cruiser class at the bmx track. The chainstays are short enough for quick acceleration, although it could be shorter. However, it is not a purebred BSX or bmx track racing frame, so that’s not so important. Manualling and wheelying on this bike is a breeze – the weight balance front and rear being pretty even and low. Finding the balance point and holding it was easy.
In all cases the cromo frame took the sting out of all landings. Going large, I’d prepare myself to handle the shock, yet the frame would unexpectedly take up some of it and make touching down so much sweeter an affair. Manualing stairs and drops to manuals were handled with more ease and comfort. Entering corners hard seems to torque up the frame and it positively snaps out of the corners. It was fun having such a lively and responsive frame. Changing lines whilst going all out or bunnyhopping in the thick of action was effortless. Just react and the bike springs to do your bidding.
Street, dirt jumps, bmx track, this bike handles them all well. Performance was way above what you’d expect from its price tag. You’d quickly get addicted to its nippy, instinctive personality and gradually learn its limits. The solid and verstatile frame can be set up in many ways that would change the feel of the bike. E.g. rigid cromo fork, narrower tires, 26″ wheels / 26″-24″ combo / 24″ front and rear, lighter parts (cranks and wheels); heavier parts (3 piece cranks, marz fork, cromo seat post, cromo handlebars).
Other points to note:
The wheelbase of the bike is a bit too short for frequent BSX stuff, making handling nervous at high speed. Get yourself another frame if you’re thinking along those lines. Also, the occasional seat post extended XC ride would be tolerable… barely. Don’t try it too often.
Super Value. The CR8 is a well thought out frame with good standard angles and dimensions. It’s light ( for a cromo jump frame ), which makes it especially suited for riders with some finesse. With side gussets that can open beer bottles and a distinctive iron cross stamped out in the thick dropouts, one certainly can’t complain of any lack of character in the bike. Reviewing the frame was definitely an enjoyable period.
– 4130 double butted
– Cable layout
– Good tire clearance
– Able to run 24″/26″ wheels
– Strongly gusseted
– Good angles and lengths
– Untidy welding
– Thin paint
Top Tube…… 21″
Down Tube….. 25.8″
Head Tube….. 105mm
Head Tube Angle….. 71 degrees
Seat Tube Angle….. 72 degrees
Seat post size….. 27.2mm
Chain Stay….. 17″
Wheel Base….. 41″
Colours: Olive green or Black
Cost: SD$350 (Frame Only)
Warranty: 3 years shop warranty against manufacturing defects
Available locally at: Seng Chu Hin
Test Bike Specifications:
Frame: DaBomb CR8 13.5″ ( Disc mount, adjustable bosses for 24″/26″ wheels, replaceable derailler hanger. )
Fork: Psylo C
Rear shifter and derailler: Sram XO
Crank: Truvativ Hussefelt
Chain guide: Truvativ
Pedal: DaBomb Bomb-Pedal
Rims: 24″ DaBomb prototype cromo rims
Quick Release: DaBomb ti QR
Tires: Maxxis High Roller 2.7″ (front), Duro 2.5″ (rear)
Brakes: Armor hydraulic disc brakes